DESCRIPTION: These studies extend and expand those conduct previously. These previous studies showed that age-related los in vortical volume is not uniform but differential and selective. Age-related loss in the prefrontal cortex if pronounced and associated with age-related deficits in executive functions. In contrast, age-related loss in the hippocampal formation is mild and not generally associated with memory deficits. In a subgroup of elderly adults, however, there was a significant association between hippocampal volume and explicit memory. It is hypothesized that prefrontal atrophy is associated with healthy aging, whereas limbic atrophy is associated with the beginning of cognitive pathology. The proposed studies have three goals: 1) Investigate the longitudinal course of cerebral and cognitive aging: 2) Expand the study of the relation between age-related atrophy in the prefrontal cortex and age-related decline in executive functions; and 3) Examine more closely the relation between age-related hippocampal atrophy and deficits in declarative memory after 60 years of age.